Toughest Trivia Questions On Liquid Penetrant Testing! Quiz
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Liquid penetrant inspection requires that the liquid possess a __________ surface tension.
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High
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Low
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Medium
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Surface tension is not an important requirement of the liquid
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Toughest Trivia Questions on Liquid Penetrant Testing! This type of testing is carried put on a material in order to detect any flaws in the surface or make the more visible. If you are looking to refresh your understanding on this type of testing, be sure to take the challenging quiz below. All the best and be sure to follow See moreall the steps.
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- 2.
In Canada, NDE personnel are trained and certified to which standard?
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AECB Section 18
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CWB
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CGSB 48.9712
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Ministry of Labour Codes
Correct Answer
A. CGSB 48.9712Explanation
In Canada, NDE personnel are trained and certified to the CGSB 48.9712 standard. This standard is specifically designed for non-destructive examination (NDE) personnel and covers the requirements for training, certification, and qualification of NDE personnel. It ensures that NDE personnel in Canada have the necessary skills and knowledge to perform their job effectively and safely.Rate this question:
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- 3.
The function of an emulsifier is to:
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Help the penetrant enter a discontinuity by reducing the penetrant's surface tension
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Mix directly with a fluorescent penetrant to increase its fluorescence
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Render the excess post-emulsifiable penetrant water-washable
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Blot the penetrant back to the surface to produce an indication
Correct Answer
A. Render the excess post-emulsifiable penetrant water-washableExplanation
An emulsifier is a substance that helps to mix two immiscible substances, such as oil and water. In the context of penetrant testing, an emulsifier is used to render the excess post-emulsifiable penetrant water-washable. This means that it helps to remove the excess penetrant from the surface being tested by allowing it to mix with water and be easily washed away. By rendering the penetrant water-washable, the emulsifier ensures that any indications or defects are clearly visible and not obscured by excess penetrant.Rate this question:
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- 4.
The forerunner to modern PT was known as the:
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Hot whiting method
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Oil and whiting method
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Ring method
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Water washable method
Correct Answer
A. Oil and whiting methodExplanation
The correct answer is "oil and whiting method." The question is asking for the forerunner to modern PT (Penetrant Testing) methods. The oil and whiting method refers to a technique used in the past where a penetrating oil, often mixed with a white powder called whiting, was applied to the surface of a material. This method allowed for the detection of surface defects or cracks by the oil penetrating into these areas and making them visible. This method was later refined and evolved into the modern PT techniques used today.Rate this question:
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- 5.
Pre-cleaning in PT refers to:
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Ensuring that the surface of the material is free of contaminants
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Ensuring the penetrants are free of contaminants
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Ensuring that a discontinuity is free of contaminants
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Both (a) and (c)
Correct Answer
A. Both (a) and (c)Explanation
Pre-cleaning in PT refers to ensuring that the surface of the material is free of contaminants and ensuring that a discontinuity is free of contaminants. This means that before performing penetrant testing, it is necessary to clean the surface of the material to remove any dirt, grease, or other contaminants that could interfere with the inspection process. Additionally, if there is a discontinuity or defect on the surface, it should also be cleaned to ensure that the penetrant can properly enter and highlight the defect during testing.Rate this question:
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- 6.
Dwell time is:
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The length of time the emulsifier is left on a material surface
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The length of time a developer is left on a material surface
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The length of time a penetrant is left on a material, to enter into a near-to-surface discontinuity
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None of the above
Correct Answer
A. None of the aboveExplanation
The discontinuity must be open to the surface for penetrant to enter.Rate this question:
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- 7.
The physics that enables the penetrant to enter into a discontinuity is called:
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Caterpillar force
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Gravitational force
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Capillary force
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None of the above
Correct Answer
A. Capillary forceExplanation
Capillary force is the physics that enables the penetrant to enter into a discontinuity. Capillary force is the phenomenon where a liquid is drawn into a narrow space against the force of gravity. This force is caused by the adhesive and cohesive properties of the liquid, which allow it to climb up narrow spaces, such as the cracks or discontinuities in a material. Therefore, capillary force is responsible for the penetrant being able to enter into a discontinuity.Rate this question:
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- 8.
Black-light intensity is stated as a minimum of 1000 microwatts per centimeter squared. Why?
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To provide adequate visible light in the darkened viewing booth
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The assist the operator when removing excess fluorescent penetrant from the material surface
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To cause the fluorescent dye in the penetrant to "glow"
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To ensure the fluorescent dye reaches its peak fluorescence
Correct Answer
A. To ensure the fluorescent dye reaches its peak fluorescenceExplanation
The black-light intensity is stated as a minimum of 1000 microwatts per centimeter squared in order to ensure that the fluorescent dye reaches its peak fluorescence. When the black-light intensity is at this level, it provides the optimal conditions for the dye to emit the brightest fluorescence, making it easier for the operator to detect any defects or irregularities on the material surface. This level of intensity ensures that the dye is fully activated and visible, allowing for accurate inspection and evaluation.Rate this question:
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- 9.
According to CGSB Standards, temperatures in hot air drying ovens should be maintained at
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Maximum 71 degrees Celsius
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Option 2
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16-43 degrees Celsius
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The dryer temperature should be as high as possible to allow faster drying
Correct Answer
A. Maximum 71 degrees CelsiusExplanation
According to CGSB Standards, hot air drying ovens should maintain a maximum temperature of 71 degrees Celsius. This temperature limit ensures that the drying process is effective without causing any damage or degradation to the materials being dried. It also helps to prevent any potential safety hazards that may arise from excessively high temperatures. Option 2, which suggests a temperature range of 16-43 degrees Celsius, is incorrect as it does not adhere to the specified maximum temperature limit. The statement that the dryer temperature should be as high as possible for faster drying is also incorrect as it disregards the safety and quality considerations outlined in the CGSB Standards.Rate this question:
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- 10.
Dark adaptation is stated by most codes as a minimum of three minutes. Why?
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To allow the operator's eyes time to contract for maximum seeing in the darkened inspection area
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To allow the operator's eyes time to dilate for maximum seeing in the darkened inspection area
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To allow the operator's eyes time to expand for maximum seeing of visible dye penetrant indications
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To allow the operator's eyes time to contract for maximum seeing of fluorescent dye penetrant indications
Correct Answer
A. To allow the operator's eyes time to dilate for maximum seeing in the darkened inspection areaExplanation
Dark adaptation refers to the process by which the eyes adjust to low light conditions. When entering a darkened inspection area, the operator's eyes need time to dilate, or open up, in order to allow more light to enter the eye and improve visibility. This dilation of the pupils enables the operator to see better in the darkened environment and detect any visible dye penetrant indications. Therefore, a minimum of three minutes is required to allow the operator's eyes to fully dilate and achieve maximum seeing in the darkened inspection area.Rate this question:
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- 11.
The most important property that enables the penetrant to enter into a discontinuity is:
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Flash point
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Penetrability
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Viscosity
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Surface tension
Correct Answer
A. Surface tensionExplanation
Penetrability is determined by properties such as surface tension.Rate this question:
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- 12.
Immersion dwell is used when:
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Anticipated discontinuities are shallow and wide
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There are large numbers of test parts to be inspected
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Extremely long dwell times are needed
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All of the above
Correct Answer
A. Extremely long dwell times are neededExplanation
The correct answer is "extremely long dwell times are needed." Immersion dwell is a technique used in non-destructive testing where the test part is immersed in a liquid medium for a prolonged period. This method is employed when there is a need for extended dwell times to ensure thorough inspection. The other options mentioned, such as shallow and wide discontinuities and large numbers of test parts, do not specifically require the use of immersion dwell.Rate this question:
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- 13.
"Inspection" can be performed by trainees, Level 2 and Level 3.
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True
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False
Correct Answer
A. TrueExplanation
The statement suggests that trainees, Level 2, and Level 3 individuals are allowed to perform inspections. This implies that these individuals have the necessary skills and knowledge to carry out inspections effectively. Therefore, the answer is true.Rate this question:
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- 14.
Developing time is a minimum of one-half of the penetrant dwell time.
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True
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False
Correct Answer
A. TrueExplanation
The statement suggests that the developing time should be at least half of the penetrant dwell time. This means that the time taken to develop the penetrant should be longer than the time it takes for the penetrant to dwell on the surface being tested. This is important because it allows sufficient time for the penetrant to fully penetrate any flaws or defects in the material being tested. Therefore, the statement is true.Rate this question:
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- 15.
Which of the following developers is the most sensitive?
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Dry developer
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Aqueous developer
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Non-aqueous developer
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None of the above
Correct Answer
A. Non-aqueous developerExplanation
A non-aqueous developer is the most sensitive developer among the given options. Non-aqueous developers are typically solvent-based and have a higher sensitivity compared to dry and aqueous developers. They are able to detect smaller defects and provide higher contrast images. Dry developers are typically used for magnetic particle testing and do not provide as high sensitivity as non-aqueous developers. Aqueous developers are water-based and have lower sensitivity compared to non-aqueous developers. Therefore, the non-aqueous developer is the most sensitive option.Rate this question:
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- 16.
Which of the following developers is most suitable for parts that are complex or have rough surfaces?
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Dry developer
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Aqueous developer
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Non-aqueous developer
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None of the above
Correct Answer
A. Dry developerExplanation
Dry developer is the most suitable developer for parts that are complex or have rough surfaces because it is a powdered developer that can adhere to irregular surfaces and effectively highlight any surface defects or indications. It is commonly used in non-destructive testing methods such as liquid penetrant testing to enhance the visibility of indications on the surface of the test object. Aqueous developer is a water-based developer that is more suitable for smooth surfaces, while non-aqueous developer is a developer that is not water-based and may not adhere as well to complex or rough surfaces.Rate this question:
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- 17.
Which of the following is the best reason why excessive drying of a part is not desired?
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The extra time is wasted
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The developer may lose its blotting ability
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A reduction in resolution may result
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The excess developer may be difficult to remove
Correct Answer
A. A reduction in resolution may resultExplanation
Excessive drying of a part is not desired because it can lead to a reduction in resolution. When a part is excessively dried, it can cause the details and fine features of the part to become less clear and defined. This can negatively impact the overall quality and accuracy of the part. Therefore, it is important to avoid excessive drying in order to maintain a high level of resolution in the final product.Rate this question:
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- 18.
The contrast ratios for visible penetrants and fluorescent penetrants are respectively:
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10 to 1 and 30 to 1
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6 to 1 and 300 to 1
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500 to 1 and 9 to 1
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None of the above
Correct Answer
A. 6 to 1 and 300 to 1Explanation
The correct answer is 6 to 1 and 300 to 1. This means that the contrast ratio for visible penetrants is 6 to 1, while the contrast ratio for fluorescent penetrants is 300 to 1. The contrast ratio refers to the ability of the penetrant to create a visible contrast with the background, making it easier to detect any defects or discontinuities. A higher contrast ratio indicates a better ability to detect flaws.Rate this question:
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- 19.
The notable difference between phosphorescence and fluorescence is:
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Effecting radiation
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Persistence after applied radiation
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Frequency of transmitted light
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Temperature
Correct Answer
A. Persistence after applied radiationExplanation
Phosphorescence and fluorescence differ in terms of persistence after applied radiation. Phosphorescence refers to the emission of light that continues even after the excitation source is removed, while fluorescence only emits light as long as the excitation source is present. This means that phosphorescent materials can continue to glow in the dark, while fluorescent materials stop emitting light as soon as the excitation source is turned off.Rate this question:
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- 20.
When preparing an acid solution for precleaning, you should:
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Add the acid to water
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Add the water to acid
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Mix the acid to water in equal proportions
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Add the acid to alkaline solution
Correct Answer
A. Add the acid to waterExplanation
When preparing an acid solution for precleaning, it is important to add the acid to water rather than the other way around. This is because adding water to acid can cause a violent reaction, resulting in the mixture splashing or boiling. By adding the acid to water slowly and in a controlled manner, the reaction is less likely to be hazardous.Rate this question:
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- 21.
An important function of emulsification is:
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Stop developing action
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Improve signal-to-noise ratio
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Freeze defects in position
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Reduce bleed-out time
Correct Answer
A. Improve signal-to-noise ratioExplanation
Emulsification refers to the process of mixing two immiscible substances, such as oil and water, to form an emulsion. In the context of improving signal-to-noise ratio, emulsification can be understood as a technique used in various fields, including photography and audio engineering, to reduce the amount of noise or interference in a signal. By creating a stable emulsion, the unwanted noise or interference is dispersed or suppressed, resulting in a clearer and more accurate signal. Therefore, improving the signal-to-noise ratio is an important function of emulsification.Rate this question:
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- 22.
Specific gravity is checked using a:
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Hygrometer
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Hydrometer
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Three point balance
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Litmus paper
Correct Answer
A. HydrometerExplanation
A hydrometer is used to measure the specific gravity of a liquid. It works based on the principle that the density of a liquid is directly proportional to its specific gravity. The hydrometer is a cylindrical glass tube with a weighted bulb at the bottom. When placed in a liquid, it floats and the level at which it sinks indicates the specific gravity of the liquid. Therefore, a hydrometer is the correct tool for checking specific gravity.Rate this question:
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- 23.
Dyes used in fluorescent penetrant fluoresce in the:
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Blue-green
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Yellow-green
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Red-orange
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All of the above
Correct Answer
A. Yellow-greenExplanation
The dyes used in fluorescent penetrant fluoresce in the yellow-green color. This means that when exposed to certain wavelengths of light, these dyes emit a yellow-green glow. This property is utilized in fluorescent penetrant testing, where the dye is applied to a surface and any defects or cracks in the material can be easily detected by the fluorescence.Rate this question:
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- 24.
Viscosity is measured in units called:
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Dynes/cm
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Mm/sec
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Centistokes
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Milligrams per cc
Correct Answer
A. CentistokesExplanation
Viscosity is a measure of a fluid's resistance to flow. Centistokes is a unit commonly used to measure viscosity. It represents the kinematic viscosity, which is the ratio of a fluid's dynamic viscosity to its density. The higher the centistoke value, the more viscous the fluid is. Dynes/cm is a unit of surface tension, mm/sec is a unit of speed, and milligrams per cc is a unit of density, none of which directly measure viscosity. Therefore, centistokes is the correct unit for measuring viscosity.Rate this question:
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- 25.
The sensitivity of a liquid penetrant system is determined by:
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Contrast ratios
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Colour intensity
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Ability to detect small defects
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Frequency of black-light used
Correct Answer
A. Ability to detect small defectsExplanation
The sensitivity of a liquid penetrant system refers to its capability to detect small defects. This means that a highly sensitive system can identify even the smallest flaws or imperfections in the material being tested. Contrast ratios and color intensity may contribute to the system's effectiveness, but the primary factor determining sensitivity is its ability to detect small defects. The frequency of black-light used is not mentioned in the question and therefore cannot be considered as a factor in determining sensitivity.Rate this question:
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- 26.
The amount of white light in a darkened inspection area must not exceed 2 ftc
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True
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False
Correct Answer
A. TrueExplanation
2 ftc (footcandles) = 20 luxRate this question:
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- 27.
The most important factor which determines the speed penetrant enters a discontinuity is based on viscosity.
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True
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False
Correct Answer
A. TrueExplanation
The ability of the penetrant to enter the discontinuity is based on surface tension; however, the speed at which it enters is determined by viscosity.Rate this question:
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- 28.
Black light intensity must be a maximum of 1000 microwatts per centimeter squared.
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True
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False
Correct Answer
A. FalseExplanation
Black light intensity must be a MINIMUM of 1000 microwatts per centimeter squared, not maximum.Rate this question:
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- 29.
The meniscus test is used to determine fluorescent ability in thin films.
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True
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False
Correct Answer
A. TrueExplanation
The meniscus test is a method used to assess the fluorescent ability of thin films. This test involves observing the curvature of the liquid surface in contact with the film. If the film exhibits fluorescence, it will cause a change in the shape of the meniscus. Therefore, the statement that the meniscus test is used to determine fluorescent ability in thin films is true.Rate this question:
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- 30.
Flash point values of a penetrant should be as high as possible.
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True
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False
Correct Answer
A. TrueExplanation
A high flash point value for a penetrant is desirable because it indicates that the penetrant is less likely to evaporate or ignite at lower temperatures. This is important for safety reasons, as a penetrant with a low flash point could pose a fire hazard during application or storage. Additionally, a higher flash point value ensures that the penetrant remains in its liquid state for a longer period of time, allowing it to effectively penetrate and detect flaws in the material being tested. Therefore, it is true that the flash point values of a penetrant should be as high as possible.Rate this question:
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- 31.
Contact angle relates to:
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The temperature at which a liquid will ignite and burn when exposed to an open flame
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The angle of the water spray nozzle for removing liquid penetrant
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The angle at which a liquid sits on a material surface
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None of the above
Correct Answer
A. The angle at which a liquid sits on a material surfaceExplanation
Contact angle relates to the angle at which a liquid sits on a material surface. This angle is determined by the balance between the adhesive forces between the liquid and the surface, and the cohesive forces within the liquid. A high contact angle indicates that the liquid is less likely to spread out on the surface, while a low contact angle indicates that the liquid will spread out more easily. The contact angle is important in various applications, such as determining the wettability of a surface or understanding the behavior of liquids on different materials.Rate this question:
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- 32.
A water tolerance test is used to determine:
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The exact amount of water found in a penetrant
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How much water a postemulsifiable penetrant or a hydrophilic emulsifier can tolerate before becoming unusable
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The amount of water a dry powder developer can tolerate
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None of the above
Correct Answer
A. How much water a postemulsifiable penetrant or a hydrophilic emulsifier can tolerate before becoming unusableExplanation
A water tolerance test is used to determine how much water a postemulsifiable penetrant or a hydrophilic emulsifier can tolerate before becoming unusable. This test helps to establish the maximum amount of water that can be present in the penetrant or emulsifier without affecting its effectiveness. By conducting this test, one can ensure that the penetrant or emulsifier is able to withstand a certain level of water contamination and still perform its intended function.Rate this question:
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- 33.
Why is a black light filter necessary?
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To activate the fluorescent penetrant dye
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To provide a contrasting background on the material surface
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To protect the black light bulb from scratches and breakage
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None of the above
Correct Answer
A. None of the aboveExplanation
A black light filter is not necessary to activate the fluorescent penetrant dye because the dye is activated by the UV light emitted by the black light bulb itself. It is also not necessary to provide a contrasting background on the material surface as the black light already highlights any fluorescence present on the surface. Additionally, it is not needed to protect the black light bulb from scratches and breakage as this is not its purpose. Therefore, the correct answer is "none of the above".Rate this question:
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- 34.
Which of the following is generally accepted as the most important precaution when using a solvent-removable penetrant?
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Do not apply an excessive amount of emulsifier
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Do not use insufficient rinse pressure
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Do not use excessive amount of solvent
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Both (b) and (c)
Correct Answer
A. Do not use excessive amount of solventExplanation
Using an excessive amount of solvent when using a solvent-removable penetrant can have negative effects. It can lead to excessive removal of the penetrant from the surface, making it difficult to detect any defects. This can result in false-negative results and compromise the effectiveness of the inspection process. Therefore, it is generally accepted that using an excessive amount of solvent should be avoided as a precautionary measure.Rate this question:
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- 35.
When penetrant testing, the temperature of the test area should not be lower than:
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30 degrees Celsius
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65 degrees Celsius
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10 degrees Celsius
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5 degrees Celsius
Correct Answer
A. 5 degrees CelsiusExplanation
The correct answer is 5 degrees Celsius because penetrant testing is a non-destructive testing method used to detect surface defects in materials. In order for the penetrant to effectively flow into any surface defects, the test area needs to be above a certain temperature. If the temperature is too low, the penetrant may not flow properly and the defects may not be detected. Therefore, the temperature of the test area should not be lower than 5 degrees Celsius.Rate this question:
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- 36.
Emulsifier time:
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Is important but not critical
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Is the time needed to rinse the emulsifier and excess penetrant from the surface
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Is extremely important and will greatly affect test results
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Should be as long as possible
Correct Answer
A. Is extremely important and will greatly affect test resultsExplanation
The given answer states that the emulsifier time is extremely important and will greatly affect test results. This implies that the amount of time the emulsifier is allowed to act on the surface has a significant impact on the outcome of the test. The longer the emulsifier time, the better the results are expected to be. It suggests that the emulsifier plays a crucial role in the process and should not be overlooked or rushed.Rate this question:
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- 37.
Sulphur and chlorine found in penetrants are detrimental to:
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Aluminum
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Iron
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Nickel
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Both (a) and (b)
Correct Answer
A. NickelExplanation
Sulphur and chlorine found in penetrants are detrimental to nickel. These elements can cause corrosion and damage to the surface of nickel, leading to degradation of the material. This is why it is important to avoid using penetrants containing sulphur and chlorine on nickel surfaces to maintain their integrity and prevent any potential harm.Rate this question:
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- 38.
Penetrants may be applied by:
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Brushing
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Dipping
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Pouring
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All of the above
Correct Answer
A. All of the aboveExplanation
The correct answer is "all of the above" because penetrants can be applied by brushing, dipping, or pouring. Brushing involves using a brush to apply the penetrant onto the surface, dipping involves immersing the object into a container filled with the penetrant, and pouring involves pouring the penetrant directly onto the surface. All of these methods can effectively apply penetrants depending on the specific requirements and the nature of the object being tested.Rate this question:
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- 39.
Which of the following is an advantage of fluorescent penetrants over visible dye penetrants?
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The inspection can be carried out in a well-lit area
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Smaller indications are more easily seen
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They can be used where contact with water is objectionable
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They are less sensitive to contamination of discontinuities
Correct Answer
A. Smaller indications are more easily seenExplanation
Fluorescent penetrants have the advantage of being able to detect smaller indications more easily compared to visible dye penetrants. This is because fluorescent penetrants emit a bright glow under UV light, making even small indications more visible and easier to identify during inspection.Rate this question:
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- 40.
Why is it advisable to have an ultraviolet light installed at the wash station?
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So inspection can be done without drying parts
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To speed the bleeding out of fluorescent dye penetrant
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To check the effectiveness of the wash cycle
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To determine if parts have been sufficiently covered with penetrant
Correct Answer
A. To check the effectiveness of the wash cycleExplanation
Having an ultraviolet light installed at the wash station allows for the inspection of parts without the need for drying. This is because ultraviolet light can reveal any fluorescent dye penetrant that may be present on the parts. By using the ultraviolet light, one can determine if the wash cycle has been effective in removing any remaining dye penetrant from the parts. This helps ensure that the parts have been properly cleaned and prepared for further processes or use.Rate this question:
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- 41.
Which of the following is most likely to render the postemulsification test ineffective?
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The penetrant dwell time is too long
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The developing time is too long
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The emulsifying time is too long
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None of the above
Correct Answer
A. The emulsifying time is too longExplanation
The postemulsification test is used to detect defects or cracks in materials by applying a penetrant, emulsifying it, and then removing the excess. If the emulsifying time is too long, it can cause the penetrant to be completely removed from the cracks or defects, rendering the test ineffective as it will not be able to detect any flaws.Rate this question:
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- 42.
Which of the following characteristics does not apply to liquid penetrant testing?
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This method can accurately measure the depth of a crack or discontinuity
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This method can be used for on-site testing of large parts
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This method can be used to find shallow surface discontinuities
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This method can be made more or less sensitive using different penetrant materials
Correct Answer
A. This method can accurately measure the depth of a crack or discontinuityExplanation
Liquid penetrant testing is a nondestructive testing method used to detect surface discontinuities in materials. It involves applying a liquid penetrant to the surface of the material, allowing it to seep into any surface cracks or defects, and then removing the excess penetrant. The penetrant is typically brightly colored to make it visible under UV light. However, liquid penetrant testing is not capable of accurately measuring the depth of a crack or discontinuity. It can only detect the presence of surface defects, making it more suitable for finding shallow surface discontinuities rather than measuring the depth of cracks.Rate this question:
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- 43.
Which of the following discontinuities is most likely to be missed due to improper rinse techniques?
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A forging lap
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Deep pitting
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Shallow and broad discontinuities
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The rinse technique will not affect the detection of discontinuities
Correct Answer
A. Shallow and broad discontinuitiesExplanation
Shallow and broad discontinuities are most likely to be missed due to improper rinse techniques. This is because these types of discontinuities are not as pronounced or easily visible as other types such as a forging lap or deep pitting. Improper rinse techniques can result in inadequate removal of the penetrant from the surface, making it difficult to detect these shallow and broad discontinuities.Rate this question:
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- 44.
The ability of a liquid to wet a surface is measured by contact angle, i.e. the angle between the liquid and the surface at the point of contact as the liquid advances. Good penetrants should have:
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A very small contact angle
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A very large contact angle
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A contact angle of approximately 45 degrees
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A contact angle greater than 90 degrees
Correct Answer
A. A very small contact angleExplanation
A small contact angle indicates that the liquid has a high wetting ability and can spread easily on the surface. This is desirable for good penetrants as it allows them to effectively penetrate into small cracks and crevices. A large contact angle would indicate poor wetting ability and limited penetration. Therefore, a very small contact angle is preferred for good penetrants.Rate this question:
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- 45.
The tendency of a liquid penetrant to enter a discontinuity is primarily related to:
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The viscosity of the penetrant
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The capillary forces
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The chemical inertness of the penetrant
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The specific gravity of the penetrant
Correct Answer
A. The capillary forcesExplanation
The tendency of a liquid penetrant to enter a discontinuity is primarily related to the capillary forces. Capillary forces refer to the phenomenon where a liquid can be drawn into narrow spaces or tubes against the force of gravity. In the case of liquid penetrant testing, capillary forces allow the penetrant to flow into small cracks or defects in a material, making them visible during the inspection process. The viscosity, chemical inertness, and specific gravity of the penetrant may also play a role, but the capillary forces are the main factor determining the penetrant's ability to enter discontinuities.Rate this question:
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- 46.
Acids and chromates should not be left on the surface of parts that will be inspected with a water-washable fluorescent penetrant because:
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They may prevent the penetrant from entering any discontinuities
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They may reduce the bleed-out
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They may kill the fluorescence of the penetrant
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They may produce non-relevant indications
Correct Answer
A. They may kill the fluorescence of the penetrantExplanation
Acids and chromates should not be left on the surface of parts that will be inspected with a water-washable fluorescent penetrant because they may kill the fluorescence of the penetrant. This means that if acids and chromates are present on the surface, they can interfere with the ability of the penetrant to emit fluorescent light when exposed to ultraviolet radiation. This can make it difficult or impossible to detect any defects or discontinuities in the parts being inspected. Therefore, it is important to ensure that the surface is free from any substances that may inhibit the fluorescence of the penetrant.Rate this question:
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- 47.
Both fluorescent and visible dye penetrants are identified by:
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Dwell times
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Viscosity
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Method of application
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Method of removal
Correct Answer
A. Method of removalExplanation
The correct answer is method of removal. Both fluorescent and visible dye penetrants can be identified based on the method of removal. This refers to how the penetrant is removed from the surface after the inspection process. The method of removal can vary depending on the type of penetrant used and the specific application. It is an important factor to consider as it can affect the overall effectiveness and efficiency of the inspection process.Rate this question:
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- 48.
Which of the following is the best reason why excessive drying of a part is not desired?
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The extra time required is wasted
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The developer may lose its blotting ability
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A reduction in resolution may result
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The excess developer may be difficult to remove
Correct Answer
A. A reduction in resolution may resultExplanation
Excessive drying of a part is not desired because it may result in a reduction in resolution. This means that the details and clarity of the part may be compromised, leading to a lower quality outcome.Rate this question:
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- 49.
Black light used in penetrant testing has its peak at:
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5550 angstroms (555 nm)
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4850 angstroms (485 nm)
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4250 angstroms (425 nm)
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3650 angstroms (365 nm)
Correct Answer
A. 3650 angstroms (365 nm)Explanation
Black light used in penetrant testing has its peak at 3650 angstroms (365 nm). This wavelength is specifically chosen because it falls within the ultraviolet (UV) range, which is invisible to the human eye. The fluorescent penetrant used in this testing method absorbs the UV light and re-emits it at a longer wavelength, typically in the visible range, making any defects or cracks in the material more visible. By using a black light with a peak at 3650 angstroms, the penetrant is able to fluoresce at a wavelength that is easily detectable by the human eye.Rate this question:
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Jan 24, 2024Quiz Edited by
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Feb 09, 2019Quiz Created by
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